Telephone service is an important resource for most people because it enables them to easily communicate with others over great distances. Telephone service has progressed to where a user may place a virtually unlimited number of calls per day and any one call may have a virtually unlimited duration. The constraints for placing telephone calls, such as when a call may be placed and how long a call may proceed, arise due to choices made by the telephone user rather than any constraint being inherent in the telephone-service. Although placing telephone calls is an important part of daily life, it may be desirable on occasion to control the usage of a telephone.
Several examples demonstrate how controlling telephone usage may occasionally be desirable. For instance, long distance calls increase in cost as the length of the call increases, and some individuals may inadvertently spend an excessive amount of time, and therefore money, on a particular long distance call. Furthermore, within a given household, rules may be imposed on telephone use such as the particular time of day when a call can be placed to a friend, and/or the amount of time the call to the friend may last. Enforcing such rules and preventing excessive or unauthorized use is difficult because close monitoring of the telephone must be done.
Therefore, there is a need for an improved way to place constraints on the use of telephone service.